Dressing tool



April 26, 1949.

M. (COCHRANE ET AL DRESSING .TOOL

' Filed May 10, 1946 3. Sheets-Sheet l 2f INVENTORS we? umwaiz COCHRANE ET AL DRESSING TOOL April 26, 1949.

:s Shets-Sheet 2 Filed May 10, 1946 INVENTORS g iiacejif Gxizrane amp Qffmsm -April 26, 1949. w. M. COCHRANE ET AL DRESS ING TOOL 5 Sheets-Sheet 3 Filed May 1o,' 1946 D JNVENTORS WiZZaCefl fig Patented Apr. 26, 1949 UNITED STATE DRESSI 3G TOOL Wallace M. Cochrane, Davenport, lowa and Hans A. Hanson, South Bend, Ind.

Application May 10, 1946, Serial No. 668,999

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) Claims.

The inventiondescribed herein may be manufactured and used by or for the Government for governmental purposes without the payment to usof any royalty thereon.

This invention relates to a machine tool and more particularly to a tool of the type for dressing grinding wheels. In its specific aspects the invention relates to a tool having a swingable dressingpoint adapted to dress grinding wheels having arcuate contours.

In the manufacture of various components, machining operations are followed by precision grinding operations. The grinding operations are mostsuccessfully accomplished by the use of grinding wheels having contours conforming to the desired shape of the finished component. In order thatthe utmost accuracy and precision may be obtained in work such as this, it is necessary thatthegrinding wheel be rough dressed and then finish dressed to secure the proper contour thereon. Although dressers of the general type referred to have been commonly used heretofore, such dressers ordinarily involve rather prolonged interruption of the grinding operation on the product or component and in certain instances it isnecessary to remove the grinding wheel from the grinding machine for the purpose of dressing the wheel in a. different machine.

Itis a principal object of the present inventionto provide a contour dresser constructed as an attachrnent for the machine in which the grinding. operation is being performed and to embody in such attachment a Shiftable tool support that may be moved from a work position in which the grinding wheel may be dressed to an idl position in which the dressing tool is disposed remote from the grinding wheel and out of the way of the work on which the grinding operation is being performed.

his an important object of the invention to provide means on the dressing attachment for determining the position of the dressing tool so that the contour followed by the tool will be accurately defined.

It is another important object of the invention to provide removable gaging means and to adapt theattachment to receive difierent types and sizes in such gage means.

The invention has for another object the provision of meansv for moving the dressing tool between its work position and its idle position; and the provision of simple and effective means for locking the tool in either of its positions.

Still another object of the invention is the provision of novel tool-carrying means adapting the tool for adjustment through a variety of ranges,

The foregoing and other important objects and features of the invention will become apparent asthe disclosure of a preferred form of'tl'ie vention is completely set forth in the following detailed description and accompanying sheetsof drawings in which:

Fig. 1 is a side elevation of the dressing attaehment, the view illustrating the function of the gage means in determining the position of the dressing tool;

Fig-2 isla perspective view of the gage means p Fig. 3 is a plan view of the structure shown in Fig. l, the gaging means havingb eeniremoved;

Fig. 4 is 'a fragmentary longitudinal sectional view taken on the line 4--4 of Fig. 3 and injustrating the overcenter lock for maintaining the tool in work position;

Fig. 5 is a vertical sectional view taken substantially on the line' 5- 5 of Fig. i and illustrating the relationship betweenthe main support and pivoting base; i a l Fig. 6 is a fragmentary longitudinal sectional view taken on the line 6- 6 of Fig. '3 and illustrating the means for supporting th'edressing tool; a

Fig. 7 is a transversesectionalview taken on the line l l of Fi g. 6 and illustrating one ofthe means for adjusting the dressing 0101. w

Although the present disclosurepertains in its specific aspects'to a tool for dressing grinding wheels, it willbe appreciated that certain, of the several features thereof will be found similarly applicable to machine tools of other types. Acicording1y,the disclosure herein shouldbe taken as illustrative and not limiting.

As stated above, the preferred form ofinven tion illustrated herein is provided as an attachment for a machine of the type adapted to perform grinding operations, and the attachment as such 'is embodied in such form that it maybe mounted on such machine so that it .niay be shifted from a work position in which the dress ing operationmay be performed to an idle positioniin which it will not interfere with thefunction of the machine during the grinding operation. In one particular instance, the g'rindi'ng operation is performed .in.a machine, sachets; lathe, having a horizontal bed and a horizontal rotatable spindle or chuck in which the erirlding wheel or element is carried. Portionsoff such machine are illustrated'inFigs. 1 andZ herein. lfhe reference numeral l0 designates the hori-v zontal bed and the numerals II and I2 designate respectively a rotatable spindle and a worksupporting chuck. The chuck is rotatable and includes suitable means I3 for supporting a workpiece or component I4 having a bore or similar internal recess requiring grinding on a particular contour, such contour being indicated in dotted lines by the numeral I5. The rotatable spindle II' carries for rotation therewith a coaxial grinding wheel I6 which, as best seen in Fig. 3, has an arcuate contour formed about a center and on a radius of a predetermined dimension. As will be hereinafter more fully brought out, the grinding operation in the present instance is performed by shifting the grinding wheel I6 and work I4 axially toward each other so that the grinding wheel I6 enters the component I4 and engages the contour I therein.

The dressing unit illustrated herein comprises a main support ll rigidly but removably secured by bolts I8 and I9 to a transverse tool support Ina on the bed It. The bed is provided with conventional longitudinal ways Itb and the support Illa is carried thereby for adjustment longitudinally of the axis of the spindle II. The support la is provided with means accommodating adjustment of the support H, such means taking the form of slots Ific through which the attaching bolts I8 and i9 are passed. The longitudinal extent of the support I! is transverse or normal to the axis of rotation of the grinding wheel IS. The upper surface of the support I I is formed with a guideway 20 longitudinal with respect to the support and transverse to the axis of the grinding wheel I6. For the purpose of clarity in the following description, reference to longitudinal and transverse movement will be made with respect to the longitudinal extent of the support I! unless otherwise specified.

The guideway 20 carries thereon a base member 2| having its under surface formed with a guideway that is complementary to the guideway 20. In this manner the base 2| is carried on the support I! for movement in a longitudinal path. The guideway in the base member 2I is provided with a bearing strip 22 of any conventional material suitably held in place by a plurality of studs 23. The support I? is provided at its end remote from the axis of the grinding wheel I6 (or the left-hand end as viewed in Figs. 1 and 3) with a transverse pivot pin 24 on which is pivoted an upstanding arm 25. As best shown in Fig. 4, the arm 25 is provided with a bore 26 and a reduced counter-bore 21 on an axis disposed longitudinally with respect to the support IT. The proximate end portion of the support I! is provided with a coaxial tapped bore 28. An adjusting screw 29 is passed through the bores 26 and 2'! and is threaded into the tapped bore 28 in the suport IT. A coil spring 30 encircles the adjusting screw 29 and is contained in the larger bore 26 in the arm 25. The upper end of the arm 25 is provided with a transverse bore that receives a pivot pin 3i This pin serves to pivotally connect to the arm 25 a link 32 that extends inwardly toward the axis of the grinding wheel I6. A second link means 33, comprising a pair of parallel links 34 and an operating handle 35, is connected between the link 32 and the base member 2|, As best shown in Fig. 3, the left-hand end of the base member 2I is formed with a pair of slots 36 in whichthe right-hand ends of the links 34 are loosely fitted. A pivotpin 3! is passed through the base member 2I and the ends of the link otally carried by the base 2i.

members 34 for pivotally connecting these elements together on a transverse axis. The link means 33 is pivotally connected intermediate its ends to the right-hand end of the link 32, the pivot being provided on a transverse axis by pivot means in the form of a bolt 38.

From the description thus far it will be seen that the base 2I may be shifted between two positions by means of the handle 35. When the handle 35 is raised, the links 32 and 33 will pivot upwardly about the axis of the bolt 38 and the base member will be drawn to the left-hand end of the support H or to a position remote from the axis of the grinding wheel IS. The support Il is provided near its left-hand end with stop means in the form of an upright pin 39. When the base member 28 moves to the left, a cutout portion ii thereof engages the stop pin 39. When the handle is in its down position, as shown in Figs. 1, 3 and i, the base 25 is in its right-hand position. This position of the base is determined by adjustable stop means provided at the righthand end of the support ll. As best shown in Fig. i, this end of the support is provided with an upstanding crossbar ti rigidly secured to the support by a pair of bolts 42 (only one of which is shown). An adjusting member in the form of a bolt 83 is threaded into the crossbar M for adjustment on a longitudinal horizontal axis. An abutment member 42 5 is rigidly carried at the right-hand end of the base 2i and cooperates with the adjusting bolt 43 for the purpose of determining the right-hand or Work position of the base 2i. The relationship between the linkage 25-32-33 is such as to provide an overcenter lock for the base 2I when the base is in the position shown in Fig. l. The resilient mounting of the arm 25 on the end of the support I! accommodates variations in adjustment of the adjusting screw 43 at the other end of the support I! and in addition contributes to the effectiveness of the overcenter lock,

As best shown in Fig. 5, the base 2| is provided with pivot means on a vertical axis. For this purpose the base Zl is formed with a vertical bore 45 which is fitted with a bushing or bearing 46. A secondary base or tool-carrying member 41 is mounted on the base 2i and has a depending pivot member is rigidly secured thereto and rotatably carried in the bearing it. A circular cap 48 is secured to the pivot member 48 at the bottom thereof and is retained in a counter-bore 50 at the end of the bore 45 in the base 2I. The axis of the bearing 48 is coincident with the center of the circle on which the contour of the grinding wheel I6 is formed. When the support ll is mounted on the support IOa, the arrangement is such that the support H is pre-set so that this coincidence of axis results, pro-per positioning of the support ll being made by means of the slots We and bolts I8 and 9 and proper locating of the support liia being made on the ways Illb of the bed H3.

The tool-carrying member 45 is thus freely piv- The member 41 is provided with a platform or bed 5! extending horizontally and longitudinally at one side of the vertical axis through the pivot 38. The platform 5! is preferably in the form of a guideway that cooperates with the longitudinal guideway of a tool supporting member 52. A bearing strip 53 of any suitable material is provided between complementary faces of the guideways and is secured therein by a plurality of studs 54. The tool-supporting member 52 is thus carried by the member the upper end of the cylindrical member '56.

aecsgosc 4.1 for longitudinal movement toward and away from the axis of the pivot it. A locking element in the form of a screw and handle 55 operates between the members d"! and 52 to maintain the adjusted position of the member 52.

As best shown in Fig. 6, the member M is provided at its right-hand end with a longitudinal bore 56 that opens inwardly of the member to a cutout portion 51 formed therein. The bore 56 provides means in the member ll for rotatably carrying a longitudinal adjusting screw This screw is provided intermediate its ends with an integral collar 59 that fits in a counter-bore so adjacent the bore 56. A short flanged sleeve 6! is snugly fitted in the counter-bore 56 and is retained therein by a cross pin 52. The pin 52 holds the flanged sleeve ti against rotation and against axial displacement with respect to the member ll, and the flanged sleeve Bi turn holds the adjusting screw 53 against axial shifting although permitting rotation thereof. The righthand end of the screw has keyed thereto an adjusting knob The outer extreme end of the screw 53 is threaded and receives a pair of locking nuts Hi for holding the adjusting knob 63 in place on the screw. As best shown in Figs. 1 and 3, the adjusting knob has a portion thereof knurled and an adjacent portion provided with a plurality of circumferentially spaced indexing graduations. flanged sleeve 65 is provided with a single index mark, as at 85, for cooperation with the graduations on the adjusting knob 53. The inner end of the adjusting screw 53 is formed as a threaded shank 86 which passes through the threaded bore of a nut iii. The nut is provided with a vertical shank portion at which fits a short vertical bore 59 in an intermediate portion of the tool-supporting member 52. The shank portion E8 of the nut 61 is formed with a tapped bore "it that receives a threaded cap screw H, the member 52 being vertically bored as at it to receive the cap screw. The upper end of the bore i2 is enlarged as at 73 to receive the head of the cap screw. The construction described mounts the nut 6i rigi iy on the member t2 and adapts the nut for cooperation with the adjusting screw 58 for the purpose The upper central portion of the 1 of longitudinal adjustment of the member J2 on Y the member Ill.

The upper forward portion of the member 52 is formed as a sleeve "l lp-rovided with a vertical bore '65. This sleeve carries therein a vertical cylindrical member it having its upper end threaded as at "ll and its lower end threaded as at l8. A knurled nut it is threaded on the upper threaded portion ill and a similar nut is threaded on the lower threaded portion '48 (Fig. 6). The nuts it and 89, in addition to their function of securing the cylindrical member "lii rigidly to the sleeve portion id of the member 52, serve also as means for varying the vertical position of the sleeve 76 in the member 52. The upper end of the cylindrical member if is enlarged and the top surface thereof is provided with an arcuate recess 8| normally longitudinal with respect to the support ll. This recess serves to seat a tool 82 on In the present instance, this tool is shown as a diamond point dresser particularly adapted for dressing grinding wheels such as the grinding element It referred to above. The cylindrical member H5 is axially bored, as at SS, and receives an elongated securing member 84 in the form of an eyebolt having an upper eye portion 85 and a lower threaded shank 86. The eye encircles and numeral til.

6 receives the dressing tool 82,v and a nut 8!, threaded on the threaded shank 86, serves to secure the tool 82 in position on the cylindrical member [5.

As best shown in Fig. 7, the cylindrical member is longitudinally out out intermediate its ends in an arcuate fashion on opposite sides of a plane passed through the center thereof to provide an ear or lug 88. The sleeve portion M of the member 52 provided with a pair of. coaxial tapped bores 89 in each of which is received an adjusting screw d8. These screws respectively engage opposite sides of the lug or ear 83 and may be selectively rotated to vary the angular position of the cylindrical member iii about its axis in the member 52.

As best shown in Fig. 3, the member 4'! is provided with a second platform structure designated generally by the numeral M. This platform has a accurately machined top surface 92 and four sides 93', 9d, 95 and S6. The sides 93 and 96 are accurately machined and serve as locating means for a gaging unit, as will appear below. As best shown in Fig. 1, the side 94 is disposed at a slight angle to the top surface 92. As best shown in Fig. 5, the side 95 is similarly angled. The top surface and side portions of the platform 9| are formed as stated for the purpose of locating on the member d7 means for accurately determining the correct location of the dressing tool 82.

The arrangement or" the dressin unit is such that the vertical axis about which the member 4'! pivots on the base 2| is coincident with the axis about which the arcuate contour of the grinding wheel is formed. The sides and top of the platform iii cooperate with complementary portions on gage means removably mountable on the platform for gaging the position of the tool 82. The main component of the gaging means is illustrated in perspective in Fig. 2 and is designated by the This element is shown in position on the platform ill in Fig. 1. As best shown in Fig. 2, the element 9? includes at one side thereof pair of depending locating lugs 92 A plurality of similar locating lugs 99 is provided at a front edge of the element ill. When this element is mounted on the platform iii, the under surface thereof seats on the top surface 912 of the platform 9% and the locating lugs 98 and 99 respectively seat against the sides or edges 93 and 96 of the platform. The remaining side portions of the element d? are respectively provided with depending ears 1% and EM. Locking screws 22 and are respectively threaded into the ears I00 and it i. As best shown in Fig. 1, the shank portions of the locking screws H62 and ltd respectively engage the angled sides or edges 96 and 95 of the platform 9! and serve as means for rigidly mounting the element ill on the platform.

The upper right-hand portion of the element is out out as at id ito provide a seat'for a removable gage block Hi5. This gage block is preferablyattached by a short length of chain Hit to the element 91 to prevent loss thereof. The dimensions of the block 5535 are determined according to the radius of the particular grinding wheel to be dressed. In the present instance, the block lid is sized on the basis of the radius of the are forming the contour of the grinding Wheel 18. The block-receiving seat 104 is provided at the vertical face thereof with an index element Ill! (Fig. 2). The vertical edge of this element will, when the gage element d! is correctly positioned on the platform 9!, be aligned with the projected vertical axis through the vertical pivot -58 between the member 41 and the base 2 l It will be under- 7 stood that the components of the platform 9I and of the gage element 91 are initially machined so that the alignment between the axis of the pivot 48 and the index element I! is accurate.

When the handle 35 is raised to Withdraw the dressing unit to its idle or left-hand position, the base 2| moves to the left and uncovers a vertical bore I08 in the support I! (Figs. 1 and 3). A stop pin I09 attached by a chain Hi) to the support I7 is insertable in the bore I08 and serves as a lock to prevent accidental return movement of the unit to work position.

Operation The support I! is first located on the bed I0 so that the vertical axis of the bearing 48 is coincident with the center of the curve of the grinding wheel I6. Proper positioning of the support I! is accomplished by means of the adjustments provided by the slots I0c in the support Ma and the ways I0b on the bed I0. This location is made in the usual manner with appropriate measuring instruments and gages and is permanent as far as concerns the particular dressing operation. The tool 82 is then correctly positioned by means of the gage element 97 and gage block I05, after which the gage element 97 is removed from the platform 9! so that the dressing operation may be performed on the grinding wheel I5. During this phase of operation of the unit, the handle 35 is down as in Fig. 1 and the unit is in its work position; that is, in such position that the member 4'! may be swung about the vertical axis provided by the bearing 48, with the dressing tool 82 properly positioned to dress the desired contour on the grinding wheel I0. After the dressing operation is complete, the handle 35 is raised and this withdraws the unit to its left-hand or idle position out of the way of the grinding operation.

It will be necessary, of course, to locate the dressing tool 82 properly before the dressing operation can be performed. To accomplish this re sult it is desirable that the dressing unit be moved to its idle position. The gage element 97 is then located on the platform 9| by the means heretofore described and the locking screws I02 and I03 are tightened so that there is no relative movement between the gaging element 9'! and the platform 9|. Before the block I is placed on the seat I04, the adjusting knob 63 is rotated so that the tool-carrying member 52 is run in toward the gage element 97 to a point at which the height and longitudinal alignment of the dressing tool may be determined. The upper point of the index element I01 determines the proper height of the tool 82. Adjustments are made by means of the nuts I9 and 80 so that the tool 82 is accurately positioned vertically. Adjustments made by the adjusting screws 90 will correctly position the tool 82 with respect to angularity so that the longitudinal center line of the tool is aligned with the index element WI. The adjusting knob 63 is then backed oif to allow sufiicient room for the mounting of the gage block I05 on the gage block seat I04. The member 52 is then run back in by means of the adjusting knob 63 until the point of the tool just contacts the side of the gage block I05 (Fig. 1). The gage block I05 is made preferably square so that no error can occur in the mounting thereof in the seat I04. As previously stated, each dimension of the block I05 equals the radius of the contour of the grinding wheel I6. When a grinding wheel of larger or smaller radius is used, a gage block of corresponding size is substituted for the block I05. The adjustments thus made are secured and the gage element 91 and block 25 are preferably removed. The dressing unit is then returned to work position and it is now ready to perform the dressing operation on the grinding wheel I6. The spindle II that mounts the grinding wheel I6 is retractable and thus the grinding wheel It may be moved into and out of the path of movement of the dressing unit as the unit is moved between work and idle position. ihe operator of the machine merely swings the unit back and forth about the vertical pivot 40 until the grinding Wheel I6 is satisfactorily dressed.

It will be seen from the foregoing that a simple and accurate dressing unit has been provided for the purpose of accomplishing precision dressing of contoured grinding tools. It will be appreciated, of course, that certain of the features of the invention are similarly applicable to the use of other tools in other instances. Likewise, it will be understood that the foregoing description and illustrations of the invention pertain to only a preferred embodiment thereof and that numerous modifications and alterations may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

We claim:

1. in a machine for dressing grinding wheels and the like, the combination of a base member, a secondary base member, means mounting said secondary base member on said base member for pivoting about a vertical axis, a tool support, means mounting said tool support on said secondary base member for longitudinal adjustment through a horizontal path toward and away from the aforesaid vertical axis, a tool-carrying member, means mounting said tool-carrying member on said tool support for adjustment with respect to said vertical axis, a dressing tool carried by said tool-carrying member and normally positionable in a predetermined position with respect to the aforesaid vertical axis whereby when said secondary base member is pivoted on said vertical axis said tool will be swung in an are having said first vertical axis as its center, gage means remova-b-iy carried by said secondary base member for determining the desired position of said tool with respect to said vertical axis, said means including a member removably carried by said secondary base member and having a seat constructed and arranged to lie in close proximity to said tool, means on said seat for aligning said seat with said vertical axis, means on said seat for indicating correct longitudinal alignment of said tool with said vertical axis, and a removable gage block positionable between said seat and said tool for determining the distance between said vertical axis and said tool.

2. In a machine for dressing grinding wheels and the like, the combination of a bas member, a secondary base member, means mounting said secondary base member on said base member for pivoting about a first axis, a tool support, means mounting said. tool support on said secondary base member for adjustment through a path toward and away from the aforesaid axis, a toolcarrying member, means mounting said toolcarrying member on said tool support for adjustment with respect to said axis, a dressing tool carried by said tool-carrying member and normally positionable in a predetermined position With respect to said axis whereby when said secondary base member is pivoted on said axis the dressing point of said tool will be swung in an are having said axis as its center, gage means retool for determining the distance between said axis and said tool.

3. In a machine for dressing grinding wheels and the like, the combination of a base member, a secondary base member, pivot means mounting said secondary base member on said base member, tool support, means mounting said tool support on said secondary base member for adjustment through a path toward and away from the axis of said pivot means, a tool -..,rrying member, means mounting said tool-carrying member on said tool support for adjustment in a path paralleling said axis, a dressing tool, means mounting said tool on said tool-carrying member, said axis, gage means removably carried by said base member for determining the desired position of said tool with respect to said axis, said means including amember carried by said secondary base member and having a seat constructed and arranged to lie in close proximity to said tool, means on said seat for aligning said seat with the aforesaid aXis, means on said seat for setting the position of said tool-carrying member, and a removable gage blockpositionable between said seat and said tool for determining the distance between. said axis and said tool.

l. In a machine for dressing wheels and the like, the combination of a base member, a secondary base member, means mounting said secondary base member on said base member for pivoting about a vertical axis, a toe-l support, means mounting said tool support on said secondary base member for longitudinal adjustment through a horizontal path toward and away from. the aforesaid vertical axis, a tool-carrying member, means mounting said tool-carrying member on said tool support for adjustment, a dressing too-l carried by said toot-carrying member and having" a dressing point normally positionable in a predetermined position with respect to the aforesaid vertical axis so that the dressing point of said tool may be swung in an are having said vertical axis as its center when said base member is pivoted on said vertical aXis, gage means removably carried by said base member for detel ning the desired. position of the dressing point of said dressing tool with respect to said vertical axis, said means including a member carried by said secondary base memb r and having a g-ageblock-receiving portion constructed and arranged to lie in close proximity to said dressing tool, means on gage-blocxu'eceiving portion for aligning gage-bloc;--receiving portion with the aforesaid vertical axis, means on said gage-block-reoeiving portion for indicating correct longitudinal alignment of i tool with said vert cal axis, and. a removable gage block positionable between said gage-block-receiving portion and said dressing tool for deterthe between the aforesaid vertical axis and the dressing point of said tool.

In a machine tool, the combination of base member, a secondary base member, means mounting said secondary base member on said base member for pivoting about a first vertical.

axis, a tool support, means mounting said tool support on said base member for longitudinal adjustment through a horizontal path toward and away from the aforesaid vertical axis, a toolcarrying member, means mounting said toolcarrying member on said tool support for angular adjustment about a vertical axis paralleling the aforesaid first vertical axis, a tool carried by said tool-carrying member, means mounting said tool on said tool-carrying member for vertical adjustment, gage means removably carried by said base member for determining the desired position of said tool, said means including a member removably mountable on said secondary base mem her and having a seat constructed and arranged to lie in close proximity to said tool, means on said seat for aligning said gage-block-receiving portionv with the aforesaid first vertical axis, means on said seat for indicating correct vertical adjustment of said tool means on said seat for indicating correct angular adjustment of said tool, and a removable gage block positionable between said seat and said tool for determining the distance between the aforesaid first vertical axis and said tool.

6. 'In a machine tool, the combination of a base member, a secondary base member, pivot means mounting said secondary base member on said base member, a tool support, means mountin said tool support on said secondary base member for adjustment through a path toward and away from the axis of said pivot means, atoolcarrying member, means mounting said toolcarrying member on said tool support for adjustment laterally of and in a longitudinal path paralleling said axis, a tool carried by said toolcarrying member, gage means removably carried by said secondary base member for determining the desired position of the point of said tool with respect to said first vertical axis, said means including a member carried by said secondary base member and having a seat constructed and arranged to lie in close proximity to said 'tool, means on said seat for aligning said gage-block-receiving portion with the aforesaid axis, means on said gage-block-receiving portion for indicating correct lateral positioning of said tool, means on said seat for indicating correct longitudinal positioning of said tool, and a removable gage block positionable between said seat and said tool for determining the distance between the aforesaid axis and said tool.

'7. In a machine tool, a base member, a seoondary base member, means including a pivot on a vertical axis mounting said secondary base member on said base member for pivotal movement, a first platform on said base member at one side of said vertical axis and including a horizontal guideway, a second platform at the other side of said vertical axis diametrically and opposite said first platform, a tool support including means cooperable with the guideway on said first platform for mounting a tool on said secondary base member for movement toward and away from said vertical axis, means for adjusting the position of said tool support on said first platform, a tool, means carrying said tool on said tool support for adjustment with respect thereto and with respect to said vertical axis, a removable gage support mountable on said second platform, and gage means supportable on said gage support and constructed and arranged to gage a predetermined desired position of said tool.

8. In a machine of the class described, a sup-Q port, abase member carried by said support for movement from a work position to an idle position, a bracket on said support and spaced from said base member to the idle position side thereof, a link pivoted at one end to said bracket and extending toward said base member, a second link pivoted at one end to said base member and extending said first link, means pivotaliy interconnecting said links, and means for pivoting said links about said pivot means for effecting movement of said base member between work and idle positions.

9. In a machine of the class described, a support, a base member carried by said support for movement from a work position to an idle position, a bracket on said support and spaced from said base member to the idle position side thereof, a link pivoted at one end to said bracket and extending toward said base member, a second link pivoted at one end to said base member and extending said first link, means pivotally interconnectin said links, means for pivoting said links about said pivot means for effecting movement of said base member between work and idle positions, and means for locking said base member to said support in said idle position.

10. In a machine of the class described, a support, a base member carried by said support for movement from a work position to an idle position, a bracket on said support and spaced from said base member to the idle position side thereof, a link pivoted at one end to said bracket and extending toward said base member, a second link pivoted at one end to said base member and extending said first link, means pivotally interconnecting said links, means for pivoting sai-d links about said pivot means for eifecting movement of said base member between work and idle positions, and means for locking said base member to the support in said work position.

11. In a machine of the class described, a support, a base member carried by said support for movement from a work position to an idle position, a bracket on said support and spaced from said base member to the idle position side thereof, a link pivoted at one end to said bracket and extending toward said base member, a second link pivoted at one end to said base member and extending said first link, means pivotally interconnecting said links, means for pivoting said links about said pivot means which said links are connected together for efiecting movement of said base member between work and idle positions, means for locking said base member to said support in said idle position, and means for locking said base member to said support in said work position.

12. In a machine of the class described, a support, a base member carried by said support for movement from a work position to an idle position, a bracket on said support and spaced from said base member to the idle position side thereof, a secondary member pivoted at one end to said bracket for movement toward and away from said bracket and including a pivot at its other end, spring means for urging said secondary member toward said bracket, a first link pivoted at one end to the pivot of said secondary member and having a pivot at its other end, a second link pivoted to the pivot of said first link and having a pivot at its other end, means including the pivot of said second link for connecting said second link to said base member, said links being normally positioned when the base is in work position so that said pivotal connections thereof to each other and to said bracket and base member to provide an over-center lock and said links and secondary member and spring means being constructed and arranged to maintain said overcenter lock on said links, means for pivoting said links to break said lock and to efiect movement of said base member toward said bracket, and means including an opening in said support and a removable pin cooperable therewith for looking said base member in its said idle position.

13. In a machine of the class described, a support, a base member carried by said support for movement from a work position to an idle position, a bracket on said support and spaced from said base member to the idle position side thereof, a secondary member pivoted at one end to said bracket for movement toward and away from said bracket and including a pivot at its other end, spring means for urging said secondary member toward said bracket, a first link pivoted at one end to the pivot of said secondary member and having a pivot at its other end, a second link pivoted to the pivot of said first link and having a pivot at its other end, means including the pivot of said second link for connecting said second link to said base member, said links being normally positioned when the base is in work position so that said pivotal connections thereof to each other and to said bracket and base member to provide an over-center lock and said links and secondary member and spring means being constructed and arranged to maintain said overcenter lock on said links, and means for pivoting said links to break said lock and to effect movement of said member toward said bracket.

14. Tool-carrying means comprising a tool support, means forming a bore in said support, a carrier angularly and axially movable in said bore and having opposite end portions projecting respectively at opposite ends of said bore, a pair of adjusting members, one for each end portion and cooperable therewith and with the support to adjust said carrier axially and to hold said carrier against axial displacement with respect to said support, means providing an ear rigid on said carrier, means cooperable with said ear to move said carrier angularly with respect to said support and to lock said carrier in any of several angularly adjusted positions, means forming an axial bore through said carrier, a tool-mounting member inserted in said bore in said carrier, means for mounting a tool on said member, and means for securing said member to said carrier.

15. Tool-carrying means comprising a tool support, means forming a bore in said support, a cylindrical carrier angularly and axially movable in said bore and having opposite, threaded end portions projecting respectively at opposite ends of said bore, a pair of threaded adjusting members, one for each threaded end portion and cooperable therewith and with the support to adjust said carrier axially and to hold said carrier against axial displacement with respect to said support, means forming an ear integral with said carrier and intermediate the opposite ends thereof, said ear being disposed in a plane passed through the axis of said carrier, means forming a pair of opposed, aligned, tapped bores in said support on an axis normal to and intersecting said ear, a pair of adjusting screws, one in each tapped bore and engaging a proximate side of said ear, said screws being cooperable with said ear to move said carrier angularly with respect to said support and to lock said carrier in any REFERENCES CITED The following references are of record in the file of this patent:

5 UNITED STATES PATENTS Number Name Date 1,563,900 Gardner et a1 Dec. 1, 1925 1,754,630 Klamp et a1. Apr, 15, 1930 10 2,392,668 Helding Jan. 8, 1946 

